1. Field of the Invention
This invention relates in general to an apparatus and method for introducing hypergolically reactive components into a combustion chamber and, in particular, to a new and useful arrangement for the production of rotational energy which comprises means for introducing two hypergolically reactive propellant components onto an impeller having passages which discharge substantially tangentially into a combustion zone.
2. Description of the Prior Art
With the known rotational burners for combustion chambers which are activated with atmospheric oxygen, the primary combustion oxygen flows over the impeller vanes into the combustion chamber and thereby atomizes the injected propellant. A combustion between the propellant and the oxygen of the atmosphere does not take place in the interstitial spaces of the whirling flow of gases. With the known rocket propulsion chamber constructions which employ combustion fuel and oxygen it is common to use a cooling medium for cooling the inside of the combustion chamber wall, for example a medium such as water which does not actively participate in a combustion chamber process. Such a medium is fed in a whirling stream into the combustion chamber through a ring slot having an axially directed opening in order to insure that the medium has a secure adhesion to the interior of the combustion chamber. U.S. Pat. No. 2,654,997 indicates a construction with a whirling flow of cooling medium alongside the interior of the combustion chamber and both propellant components are fed at the periphery of the chamber tangentially therealong. With this construction, the rotational flow is maintained in a central region of the combustion chamber in order to cause a return gas current flow as a consequence of the depression which occurs there, so that the path of the final combustion and also the constructive length of the combustion chamber is contracted and the very hot core of the combustion flame in the center of the combustion chamber is stabilized mechanically in terms of current flow. With such a construction, the final combustion of the combustion mixture toward the inside of the combustion chamber is guaranteed and the combustion chamber wall remains protected from thermal damage. Even though with the known construction there is a whirling tangential flow of the propellant component, such a whirling flow is insufficient in many cases and it is not intensive enough. As indicated in U.S. Pat. No. 3,169,368, additional torque chambers are arranged before the main combustion chamber in order to form compact rotational currents in these chambers which continues over the overflow opening into the main combustion chamber. Even with such a construction, however, the kinetic energy contained in the propellant components is only sufficient for the required turbulance in the main combustion chamber because an ignition of the mixture is only provided for, or is only desirable, in the main combustion chamber. The kinetic energy which is effective in the direction of the circumference amounts to only a fraction of the energy which is freed in all possible directions by the reaction of the propellant components in the main combustion chamber. These gases which expand in all directions, however, do not permit the necessary generation of rotational current in the main combustion chamber for the formation of a central return flow.
In accordance with the present invention, the disadvantages of the prior art constructions are overcome and a construction is provided to guarantee an intensive whirling propellant and gas flow. This is provided in accordance with the invention by an arrangement of impeller vanes in a radial or substantially radial plane with flow ducts defined between the vanes which are directed tangentially to the combustion chamber periphery. The propellant components are directed into the flow passages where they interact or at least partially pre-react. The propeller vanes are arranged on a propellant obturator head which projects centrally into the combustion chamber from the closed or front end thereof. The propellants are fed radially into the inner ends of the flow ducts defined between the impeller blades.
In order to achieve at least a local condensation of the propellants for their fast reaction, the impeller vanes are curved in such a way that a depression area is formed by means of flow currents or eddies on their rear sides. In the depression area there are provided openings through the blades which provide flow passages between adjacent ducts through which partial amounts of centrifugally accelerated propellants are passed from one impeller duct into a condensation zone of the other impeller duct.
According to a further feature of the invention, the propellant components are fed coaxially to each other into the impeller ducts and the oxygen or oxygen carrier is supplied radially inwardly of the fuel propellant.
A further embodiment of the invention comprises the arrangement of the impeller vanes in the combustion chamber wall. In the formation of this embodiment, it is advantageous to provide propellant ring conduits having discharge openings extending into the impeller ducts and which advantageously include more than one aligned drillings which are oriented so that their discharges intersect.
In a further embodiment of the invention, the combustion chamber wall is provided with coolant ducts along which is conveyed a propellant component especially oxygen in order to permit the coolant ducts to discharge into the impeller ducts through discharge openings defined around the ring conduits.
In accordance with the method of the invention, a plurality of propellant components are directed into the closed end of a rocket engine combustion chamber onto the surface of a rotating impeller which includes radially extending flow passages, and wherein the impeller is rotated to hurl the components along the passages and to discharge them substantially tangentially into the combustion chamber, and wherein flow from one adjacent passage to another is provided to pass the propellant from one impeller duct into a condensation zone of another impeller duct.
With the invention, the general advantage of achieving an intensive whirling flow with high energy content takes place as a consequence of the reaction of the propellant components or at least a pre-reaction which takes place in the individual impeller passageways or ducts of the impeller. The resultant high energy of these components are directed in a substantially peripheral direction. The individual impeller passages or ducts are similar to a prechamber of a diesel motor, for example, which has a gas emission substantially directed to the periphery. An intensified whirling flow does not only affect the combustion and maintaining of a strong central return current flow, but also contributes to the formation of a rotational symmetric whirling flame combustion with radially outwardly diminishing temperatures. Through sufficient rotation, the cooler and consequently heavier liquid and gas particles not yet participating in the reaction process are centrifugally moved toward the combustion chamber wall and they are kept there to cool the wall until they are drawn back into the central return flow area toward the end of the combustion chamber. Local overheating of the combustion chamber wall is therefore practically avoided. By feeding the propellant components coaxially to each other and by adding the oxygen component radially inwardly onto the impeller, an intensive cooling takes place and an interreaction of the propellant components. The oxygen component is first spread over the area of the rotating impeller and provides a protective cooling film before the application of the other propellant component. The cooling action of the oxygen also causes a heating of the oxygen so that it contributes to the condensation of the propellant components. The rotating impeller maintains the combustion and contributes to the formation of an intensive return current flow of gases.
Accordingly, it is an object of the invention to provide an arrangement for the production of rotational energy, in particular, for rocket combustion chambers which are activated with hypergolically reacting propellant components which comprises an impeller rotatively mounted in the closed end of a combustion chamber and with means for directing propellant components onto the impeller to cause them to move between flow ducts defined between impeller blade portions and be discharged peripherally into the combustion chamber for hypergolic reaction therewithin.
A further object of the invention is to provide a combustion chamber construction which includes a rotatable impeller with a plurality of impeller blades arranged over a flat disk portion and which define radially extending flow ducts therebetween, and including means for directing at least two propellant components to the inner radial end of the impeller for flow through the radial flow passages, and wherein the impeller may be arranged centrally within the combustion chamber or within an exterior wall of the combustion chamber.
A further object of the invention is to provide a method of operating a combustion chamber having a rotating impeller with blades extending substantially radially defining flow passages therebetween comprising directing at least two propellant components to the inner radial end of the flow passages of the impeller while the impeller is rotated to cause the propellant components to move along the passages and to interact and wherein the oxygen propellant component is advantageously added so as to cool the surface of the impeller.
A further object of the invention is to provide an arrangement for the production of rotational energy which is simple in design, rugged in construction and economical to manufacture.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated preferred embodiments of the invention.